widget/material: move Icon to its own file and add Color; add CornerRadius to Button

widget/material/button.go

@@ -6,7 +6,6 @@ package material
 import (
 	"image"
 	"image/color"
-	"image/draw"
 
 	"gioui.org/f32"
 	"gioui.org/io/pointer"
@@ -16,7 +15,6 @@ import (
 	"gioui.org/text"
 	"gioui.org/unit"
 	"gioui.org/widget"
-	"golang.org/x/exp/shiny/iconvg"
 )
 
 type Button struct {
@@ -25,26 +23,18 @@ type Button struct {
 	Color        color.RGBA
 	Font         text.Font
 	Background   color.RGBA
-
+	CornerRadius unit.Value
 	shaper       *text.Shaper
 }
 
 type IconButton struct {
 	Background color.RGBA
+	Color      color.RGBA
 	Icon       *Icon
 	Size       unit.Value
 	Padding    unit.Value
 }
 
-type Icon struct {
-	src  []byte
-	size unit.Value
-
-	// Cached values.
-	op      paint.ImageOp
-	imgSize int
-}
-
 func (t *Theme) Button(txt string) Button {
 	return Button{
 		Text:       txt,
@@ -57,18 +47,10 @@ func (t *Theme) Button(txt string) Button {
 	}
 }
 
-// NewIcon returns a new Icon from IconVG data.
-func NewIcon(data []byte) (*Icon, error) {
-	_, err := iconvg.DecodeMetadata(data)
-	if err != nil {
-		return nil, err
-	}
-	return &Icon{src: data}, nil
-}
-
 func (t *Theme) IconButton(icon *Icon) IconButton {
 	return IconButton{
 		Background: t.Color.Primary,
+		Color:      t.Color.InvText,
 		Icon:       icon,
 		Size:       unit.Dp(56),
 		Padding:    unit.Dp(16),
@@ -114,6 +96,7 @@ func (b IconButton) Layout(gtx *layout.Context, button *widget.Button) {
 		layout.UniformInset(b.Padding).Layout(gtx, func() {
 			size := gtx.Px(b.Size) - 2*gtx.Px(b.Padding)
 			if b.Icon != nil {
+				b.Icon.Color = b.Color
 				b.Icon.Layout(gtx, unit.Px(float32(size)))
 			}
 			gtx.Dimensions = layout.Dimensions{
@@ -140,35 +123,6 @@ func (b IconButton) Layout(gtx *layout.Context, button *widget.Button) {
 	st.Layout(gtx, bg, ico)
 }
 
-func (ic *Icon) Layout(gtx *layout.Context, sz unit.Value) {
-	ico := ic.image(gtx.Px(sz))
-	ico.Add(gtx.Ops)
-	paint.PaintOp{
-		Rect: f32.Rectangle{
-			Max: toPointF(ico.Size()),
-		},
-	}.Add(gtx.Ops)
-}
-
-func (ic *Icon) image(sz int) paint.ImageOp {
-	if sz == ic.imgSize {
-		return ic.op
-	}
-	m, _ := iconvg.DecodeMetadata(ic.src)
-	dx, dy := m.ViewBox.AspectRatio()
-	img := image.NewRGBA(image.Rectangle{Max: image.Point{X: sz, Y: int(float32(sz) * dy / dx)}})
-	var ico iconvg.Rasterizer
-	ico.SetDstImage(img, img.Bounds(), draw.Src)
-	// Use white for icons.
-	m.Palette[0] = color.RGBA{A: 0xff, R: 0xff, G: 0xff, B: 0xff}
-	iconvg.Decode(&ico, ic.src, &iconvg.DecodeOptions{
-		Palette: &m.Palette,
-	})
-	ic.op = paint.NewImageOp(img)
-	ic.imgSize = sz
-	return ic.op
-}
-
 func toPointF(p image.Point) f32.Point {
 	return f32.Point{X: float32(p.X), Y: float32(p.Y)}
 }

widget/material/icon.go

@@ -0,0 +1,64 @@
+// SPDX-License-Identifier: Unlicense OR MIT
+
+// Package material implements the Material design.
+package material
+
+import (
+	"image"
+	"image/color"
+	"image/draw"
+
+	"gioui.org/f32"
+	"gioui.org/layout"
+	"gioui.org/op/paint"
+	"gioui.org/unit"
+	"golang.org/x/exp/shiny/iconvg"
+)
+
+type Icon struct {
+	Color color.RGBA
+	src   []byte
+	size  unit.Value
+	// Cached values.
+	op       paint.ImageOp
+	imgSize  int
+	imgColor color.RGBA
+}
+
+// NewIcon returns a new Icon from IconVG data.
+func NewIcon(data []byte) (*Icon, error) {
+	_, err := iconvg.DecodeMetadata(data)
+	if err != nil {
+		return nil, err
+	}
+	return &Icon{src: data, Color: rgb(0x000000)}, nil
+}
+
+func (ic *Icon) Layout(gtx *layout.Context, sz unit.Value) {
+	ico := ic.image(gtx.Px(sz))
+	ico.Add(gtx.Ops)
+	paint.PaintOp{
+		Rect: f32.Rectangle{
+			Max: toPointF(ico.Size()),
+		},
+	}.Add(gtx.Ops)
+}
+
+func (ic *Icon) image(sz int) paint.ImageOp {
+	if sz == ic.imgSize && ic.Color == ic.imgColor {
+		return ic.op
+	}
+	m, _ := iconvg.DecodeMetadata(ic.src)
+	dx, dy := m.ViewBox.AspectRatio()
+	img := image.NewRGBA(image.Rectangle{Max: image.Point{X: sz, Y: int(float32(sz) * dy / dx)}})
+	var ico iconvg.Rasterizer
+	ico.SetDstImage(img, img.Bounds(), draw.Src)
+	m.Palette[0] = ic.Color
+	iconvg.Decode(&ico, ic.src, &iconvg.DecodeOptions{
+		Palette: &m.Palette,
+	})
+	ic.op = paint.NewImageOp(img)
+	ic.imgSize = sz
+	ic.imgColor = ic.Color
+	return ic.op
+}

widget/material/material.go

@@ -14,6 +14,7 @@ import (
 	"gioui.org/op/paint"
 	"gioui.org/text"
 	"gioui.org/unit"
+	"golang.org/x/exp/shiny/materialdesign/icons"
 )
 
 type Theme struct {
@@ -22,8 +23,11 @@ type Theme struct {
 		Primary color.RGBA
 		Text    color.RGBA
 		Hint    color.RGBA
+		InvText color.RGBA
 	}
 	TextSize           unit.Value
+	checkedStateIcon   *Icon
+	uncheckedStateIcon *Icon
 }
 
 func NewTheme() *Theme {
@@ -33,10 +37,22 @@ func NewTheme() *Theme {
 	t.Color.Primary = rgb(0x3f51b5)
 	t.Color.Text = rgb(0x000000)
 	t.Color.Hint = rgb(0xbbbbbb)
+	t.Color.InvText = rgb(0xffffff)
 	t.TextSize = unit.Sp(16)
+
+	t.checkedStateIcon = mustIcon(NewIcon(icons.ToggleCheckBox))
+	t.uncheckedStateIcon = mustIcon(NewIcon(icons.ToggleCheckBoxOutlineBlank))
+
 	return t
 }
 
+func mustIcon(ic *Icon, err error) *Icon {
+	if err != nil {
+		panic(err)
+	}
+	return ic
+}
+
 func rgb(c uint32) color.RGBA {
 	return argb(0xff000000 | c)
 }